Cheat Mode
When you purchase a newspaper always check the bottom right for the codes. There may also be others throughout the paper. Enter the following codes to activate the corresponding cheat option.

Note: Enabling cheat codes will prevent the game from being saved and will not allow achievements or trophies from becoming unlocked.

HUMILITY BEFORE THE LORD - Who? (become a nobody).
OH MY SON, MY BLESSED SON - Jack Attack (turn John into Jack, his son).
THEY SELL SOULS CHEAP HERE - Decrease bounty.
THE OLD WAYS IS THE BEST WAYS - Old School (sepia graphics).
THE ROOT OF ALL EVIL, WE THANK YOU! - Money (+$500).
IT'S MY CONSTITUTIONAL RIGHT - Gun Set 1.
I'M AN AMERICAN. I NEED GUNS - Gun Set 2.
ABUNDANCE IS EVERYWHERE - Infinite ammo.
MAKE HAY WHILE THE SUN SHINES - Infinite horse stamina.
I DON'T UNDERSTAND IMNFINITY - Infinite Dead Eye.
HE GIVES STRENGTH TO THE WEAK - Invincibility.
BEASTS AND MAN TOGETHER - Horse (spawn horse).
YOU GOT YOURSELF A FINE PAIR OF EYES - Lewis & Clark (all areas unlocked).
I WISH I WORKED FOR UNCLE SAM - Diplomatic Immunity (no bounty/wanted level).
DON'T YOU LOOK FINE AND DANDY - Sharp Dressed Man (Gentleman's suit).
I AM ONE OF THEM FAMOUS FELLAS - Become Famous.
I LOVE A MAN IN UNIFORM - Man In Uniform.
IT AINT PRIDE. IT'S HONOR - Good Guy.
YOU THINK YOU TOUGH, MISTER? - Treasure Hunter outfit.
NOW WHO PUT THAT THERE? - Coach.

Hints

Achievements
Complete each achievement to receive the allotted gamerscore:

Clemency Pays (10) - Capture a bounty alive.
Exquisite Taste (10) - Purchase a rare weapon from a gunsmith.
Friends in High Places (10) - Use a pardon letter with more than $5,000 bounty in Single Player.
Bearly Legal (5) - Kill and skin 18 grizzly bears.
Fightin' Around the World (5) - Knock someone out in melee in every saloon in the game in Single Player.
The Gunslinger (5) - Score a headshot on any enemy using Expert targeting mode.
Buckin' Awesome (10) - Break the Kentucky Saddler, the American Standardbred, and the Hungarian Half-bred.
He Cleans Up Well! (10) - Obtain the Elegant Suit.
High Roller (10) - Win over 2,000 chips in a hand of Poker.
Posse Up! (10) - Create a posse and get the maximum number of members.
Red Dead Rockstar (10) - Kill a Rockstar or someone with this achievement in a public multiplayer match.
Slow on the Draw (10) - Get 10 assists in a single Hideout in a public Free Roam session.
Hit the Trail (10) - Get from Blackwater to Escalera before sundown in a public Free Roam session.
More than a Fistful (10) - Earn $10,000 in Single Player.
Most Wanted (10) - Become a Public Enemy for 10 minutes and escape alive in a public Free Roam session.
No Dice (10) - Complete a game of Liar's Dice without losing a single die.
On the Trail of de Vaca (10) - Uncover every location on the map in Single Player.
Strange Things are Afoot (10) - Complete a task for a Stranger.
What About Hand Grenades? (10) - Get a ringer in a game of Horseshoes.
Bullseye (20) - Get 250 headshots in any game mode.
Long Arm of Marston (20) - Kill 500 enemies with any rifle, repeater, or shotgun in any game mode.
Mowing Them Down (20) - Kill 500 enemies with a mounted weapon in any game mode.
The Quick and Everyone Else... (20) - Be the top scoring player in any three consecutive FFA games in public matches.
Unnatural Selection (20) - Kill one of every animal species in the game in any game mode.
Frontiersman (20) - Obtain Legendary rank in any Single Player Ambient Challenge.
Go Team! (20) - Be on the winning team for four consecutive victories in any team based game in public matches.
Have Gun Will Travel (20) - Complete all Hideouts in a single public Free Roam session.
How the West Was Won (20) - Reach the top rank for multiplayer experience.
In a Hail of Bullets (20) - Kill 500 enemies with any pistol or revolver in any game mode.
Austin Overpowered (25) - Complete Twin Rocks, Pike's Basin, and Gaptooth Breach Hideouts in Single Player.
Evil Spirits (25) - Complete Tumbleweed and Tesoro Azul Hideouts in Single Player.
Gold Medal (25) - Earn a Gold Medal Rank for a combat mission in Single Player.
Instinto Asesino (25) - Complete Fort Mercer and Nosalida Hideouts in Single Player.
Man of Honor / Chivalry's Dead (25) - Attain highest Fame rank and either highest Honor rank or lowest Honor rank.
People are Still Strange (25) - Complete 15 tasks for Strangers.
Redeemed (100) - Attain 100% in the Single Player Game.

Additionally, there are twelve secret achievements:

That Government Boy (10) - Complete "Exodus in America".
Land of Opportunity (30) - Complete "The Assault on Fort Mercer".
The Benefits of Civilization (90) - Complete "And the Truth Will Set You Free".
Into the Sunset (100) - Complete "The Last Enemy That Shall Be Destroyed".
Sons of Mexico (40) - Complete "The Gates of El Presidio".
No More Fancy Words (20) - Complete "An Appointed Time".
Dastardly (5) - Place a hogtied woman on the train tracks, and witness her death by train.
Spurred to Victory (10) - Complete 20 story missions without switching to a new horse at a hitching post.
A Savage Soul (10) - Complete "At Home with Dutch".
Nurture or Nature? (50) - Complete "Remember My Family".
Heading South on a White Bronco (5) - Evade the US Marshals while riding the Hungarian Half-Bred horse in Single Player.
Manifest Destiny (5) - Kill the last buffalo in the Great Plains in Single Player.

Axe Master (10) - Complete all Tomahawk challenges in Single Player.
Call it a Comeback! (10) - Come back from a 2-0 deficit and win a Hold Your Own game.
Double bagger (10) - Double capture 3 times in a single Gold Rush map.
Hail Mary (10) - Get a kill greater than 35 yards with a Tomahawk.
Headhunter (10) - Kill 5 players via headshot in a single Shootout or Gang Shootout.
Legendary (10) - Reach level 50 and pass into Legend.
Original Gunslinger (10) - Get 25 Deadeye kills with Red.
Reeeeal Good (10) - Get 25 Dynamite kills with Pig Josh.
Stick and Move (10) - Get 3 kills with knives or throwing knives in a single competitive match.
Who needs Deadeye? (10) - Kill 3 or more players in a standoff or showdown.

Additionally, there are fifteen Liars and Cheats achievements:

Avatar of Death (5) - Successfully complete either round of a Stronghold map without dying.
Compulsive Liar (10) - In a full Multiplayer Liar's Dice game, win without losing a single die.
From Glue to Mon Dieu! (5) - During a Grand Prix, finish a race in first after placing last in the previous race..
One Die to Rule Them All (5) - In a Multiplayer Liar's Dice game, win with only one die left.
Over 9001 (5) - Attain over 9,001 points in a single Free Roam session.
Pa-Pa-Pa-Poker Ace (10) - In a full Multiplayer Poker game, beat the table when blinds are at maximum.
Good Call (5) - In a single Multiplayer Liar's Dice game, successfully make a spot-on call.
In A Van Down By The River (5) - In a Multiplayer Poker game, win a hand on the last card when you were losing prior.
Legion of Boom (5) - Get a triple kill while on the attacking team in Stronghold.
Master Exploder (10) - Complete the Explosive Rifle Single Player Challenge.
The Big Bluff (5) - In a Multiplayer Poker game, win a hand by forcing someone with a better hand to fold.
Peacewalker (5) - Finish a single race without getting shot or killed, and without shooting a bullet.
Put the Posse on a Pedestal (5) - Attain over 50,000 posse points in a single Free Roam session.
Triple Crown (10) - Get first place in all races in any Grand Prix.
We Must Protect This House! (10) - While on defense, do not allow the attacking team to capture any of their objectives.

Additionally, there are eight Undead Nightmare Pack achievements:

Judge A Man By The... (30) - Complete "Cure For Most of What Ails You" and "Get Back in that Hole, Partner" Survivor Missions.
Kingpin (10) - Fight off 8 unique players during your time on top during Land Grab in Multiplayer Free Roam.
Spinning Plates (25) - Have every territory saved at the same time during the Undead Nightmare.
The Downward Spiral (10) - Complete "Curious Tales from Blackwater, USA" Survivor Mission.
Mad Marston: The Trail Warrior (10) - Attain Rank 5 in all Undead Nightmare Challenges.
Six Years in The Making (10) - Find and kill a sasquatch.
Smoke that Skinwagon (10) - Make it to wave 15 in Undead Overrun Gametype in Multiplayer.
Zed's Dead, Baby (40) - Attain 100% Game Completion statistic in Undead Nightmare.

There Will Be Blood Reference
The town of Plainview is a reference to the movie There Will Be Blood main character Daniel Plainview, played by Daniel Day Lewis. Take note of all the oil rigs.

Gentleman's Attire - Complete the Rockstar Games Social Club "Skin It To Win It" challenge.
Lady's Finest - Complete the Rockstar Games Social Club "Skin It To Win It" challenge.
Posse T-shirt - Unlocked when the multiplayer community reaches an unspecified amount of money in The Strike It Rich! Rockstar Challenge.
Red Dead Redemption logo T-shirt - Open a chest northwest of Riley's Charge in a burnt down building.
Rockstar Logo T-shirt - Open a chest upstairs in the attic at the Marston Farm house at Beecher's Hope.
Sombrero - Shoot the hat off of an enemy in Expert Aim mode.

Easy Experience
Play in online Free Roam mode. Find a gang hideout and kill all the enemies, as well as the reinforcements that appear. Loot the bodies to get money and ammunition, then leave the hideout. After a short amount of time the enemies will respawn, allowing you to repeat the process as many times as desired.

Unlimited Fame and Honor
Go to Thieves' Landing and buy the elegant suite. Go in the saloon and play poker ($25). Get caught cheating by pulling the arrow to one side. You will have to duel someone. Shoot the gun out of their hand for extra fame and honor. Note: When you do this, the bullet may bounce off and hit someone else. They will start shooting at you. To make this easier, buy the house in town to save the game and get others off your back.

Crucifix
Give the nuns money whenever possible. Attaining maximum honor and fame may help. A nun will eventually approach you. She will tell you that she and the other sisters have been gathering items to help your righteous cause. She will give you a cross that makes enemies less likely to hit you with bullets. Note: You must remain honorable for this to remain in effect.

Unlock Mounts
Reach the indicated level to unlock the corresponding mount. Note: For the "Legendary" mounts, you must reach level 50, then continue to play in "Legendary" mode back at level 1 and level up again the indicated number of times.

Unlock Bureau Uniform
Get 100% game completion (all challenges, side-quests and items) to unlock the Bureau Uniform. When worn, local law enforcement and bounty hunters will ignore you.

Easy Experience
Play in online Free Roam mode. Find a gang hideout and kill all the enemies, as well as the reinforcements that appear. Loot the bodies to get money and ammunition, then leave the hideout. After a short amount of time the enemies will respawn, allowing you to repeat the process as many times as desired.

Easy Money
Find one of the bird shooting challenges. They are usually easy to find; just listen for shots and watch for a lot of birds circling in the sky. Accept the challenge and intentionally lose. The wager will then double. Repeat this until you have just enough money to make one more bet. Then, watch the sky and wait until you can see the amount of birds you need to win the bet. Accept the challenge, then go into Dead Eye mode. Take down the proper amount to win. Note: It may help to have moonshine or chewing tobacco in case you run out of Dead Eye. After you win the bet, put on your bandanna and kill the man you bet against. Loot his body and he will have the same amount of cash as the final wager. The more money you have to work with, the more you can make. It is possible to loot over $20,000 from him.

Easy Herding
When you are herding, stand far back and just ride very slowly. The herd should follow the person in front of the herd.

Avoid Reloading
Enter Dead Eye mode when you are low on ammunition. Your ammunition will be restored without the need to reload.

West Dickens Urinates
Start a mission with West Dickens that requires driving or shotgunning his carriage. When you are a few hundred yards away from the mission's starting point, press [Triangle] (PlayStation3) or [Y] (Xbox360) to jump free. Remain idle and do not get back on the carriage. Eventually West Dickens will jump off the carriage and begin urinating.

Ghost Town
Kill every person and animal in a town to have it marked as a "ghost town". Check the population sign at the town's border to check your progress. The town will remain empty for the remainder of the game. Note: Wearing the Bureau Uniform while doing this is recommended.

Save Anytime
Use the following tricks to force the game to save:

- Change the "Audio" settings in the "Options" menu.
- Purchase two horse deeds and enter your item menu. Select a deed to summon that horse. Switch horses to force the game to save.

Easy Horse Breaking
When you're breaking a horse, be it for a mission or your own personal amusement, to avoid getting thrown off the horse simply move the left analogue stick left and right repeatedly, ignoring what the game tells you to do. The horse will buck around a bit more than usual, but you'll end up breaking it successfully without the massive aggravation of doing it the standard way.

The Shawshank Redemption
To the east of Beecher's Hope you can easily spot a broken tree beside the road with a small weathered stone wall under it. This is also the location where the treasure is buried for level 9 of the Treasure Hunter challenge. The location all but identical to the location Morgan Freemans character goes to to collect his treasure in The Shawshank Redemption.